Method of heating and for controlling chemical reactions at high temperatures



Nov. 5, l 929.

1 c. FIELD 1,734,329 METHOD OF HEATING AND FOR CONTROLLING,CHEMICAL REACTIONS AT HIGH TEMPERATURES Original Filed March 1920 Patented Nov. 5, 1929 UNITED STATES PATENT OFFICE CROSBY FIELD, OF YONKERS, NEW YORK, ASSIGNOR TO CHEMICAL MACHINERY CORPORATION, A CORPORATION OF NEW YORK METHOD OF HEATING AND FOR CONTROLLING CHEMICAL REACTIONS AT HIGH TEMPERATURES Original application filed March 4, 1920, Serial No. 363,129. Divided and this application filed July 15,

1922. Serial This invention relates to an improved method for controlling chemical reactions at high temperatures, and includes the provision of means whereby certain organic or hydrocarbon materials which require a temperature greater than the boiling point of water, may

be sulphonated, nitrated, distilled, fused, or

subjected to various other chemical reactions.

In all chemical reactions the control of the temperature at which the reaction occurs is necessary in order to insure a maximum yield and the best quality of the product. Under comparatively low temperatures, which may be readily obtained by means of hot water or steam, such control is well known in the art.

When, however, high temperature control is attempted, the results so far obtained have not been satisfactory.

By the term chemical reaction in the present disclosure is meant the combination of chemicals, and in addition thereto the disassociation of chemicals by means of heat and the concentration of chemicals in their various solutions, and further, the change of chemicals from one state or atomic structure to another, as by distillation, sublimation, evaporation, concentration, precipitation, etc., and those other operations in industrial chemical processes by which chemical substances are transformed and obtained in the condition requisite to their subsequent use in the arts.

The invention comprehends an improved method whereby very delicate temperature control at low pressure may be obtained with a correspondingly large transfer of heat per surface unit. As a result of my improved method of temperature control, the required apparatus is relatively simple, may be readily installed, occupies a minimum of space and requires the attention of the operative only at infrequent intervals.

I have employed the improved method with marked success in sulphonation and distillation processes as heretofore used in the art in the production of beta naphthol, alpha haphthol, paranitraniline, anthacene, anthraquinone, acetanilid, naphthalene, phenanthrene, and believe that my invention is ap- 50 plicable to the entire family of organic mi!- terials, of which there are several thousand compounds known in the art.

In the use of mercury and its vapor as a heat transfer medium for these organic compounds, two methods of utilization are applicable; one, where the mercury itself does not come into actual contact with the substance being treated, but transfers its heat through another medium, such, for example, as steel. This method may be successfully employed in the sulphonation of naphthalene in the production of beta disulphonic acid. The other method consists in introducing the mercury vapor directly into the substance being treated, as for instance in the purification of anthracene and anthraquinone by mercury vapor distillation or sublimation in a manner similar to that in common use when superheated steam is employed as the heat transfer agent.

Mercury has a molecular weight of 200; hence it is very dense and because of such density, it is a comparatively easy matter to segregate the mercury from organic materials by gravitation. Furthermore, mercury readily forms amalgams with metals whi h are easily obtainable. Therefore, by inserting in 1parts of the apparatus where pressure might e created, metal with which the Inercury will amalgamate, there will be no danger of the mercury fumes escaping to the atmosphere and dangerously affecting persons in the vicinity. Mercury will not form an amalgam with iron or steel, nor does it wet the surface of these metals. Consequently, when it is used for the practice of my improved method which I shall now describe, a very large heat transfer per surface unit will be noted.

Having above stated the several salient features of my invention, the manner in which the improved method may be successfully carried out in ractice will be fully understood from ref drence to the accompan ing drawings in which I have illustrated one orm of apparatus which has been successfully employed in obtaining certain chemical reactions of organic materials and especially dye stufl's and intermediates thereof.

In the drawing similar reference characters designate corresponding parts throughout the several views.

In the drawing, the'figure is a diagrammatic sectional view showing one form of apparatus particularly designed for use in connection with chemical reactions involving the introduction of mercury vapor directly into the substance being treated.

Referring in detail to the drawing, 1 designates a closed kettle or vessel having a chamber 2 to receive the substance to be treated and provided with a jacket 3 for the wall of nected to the furnace chamber.

said chamber. A rotary agitator 4 is fixed upon the lower end of a shaft 5 extending into the chamber 2 and is driven through the medium of the gears 6 from any convenient source of power. The mercury is heated and vaporized in a boiler 7 arranged within a suitably constructed furnace 8. 9 indicates the source of heat which may be obtained from gas, oil, coal or other combustible fuel. The gases pass between spaced tubes 12 depending from the boiler 7 and out through the discharge 11. which is con- In order to obtain a quick heating of the mercury vertically disposed rods 12' are arranged in the boiler and extend downwardly into the tubes 12, so that only a relativelysmall quantity of the mercury will flow into said tubes and around the rods. T iese rods may extend above the level 13 of the mercury in the boiler 7 and be fixed to the top wall of the boiler as in the drawing, or the comparatively short rods may be used and wholly submerged within the mercury. It will be understood that the mercury is heated to the boiling point and converted into vapor, such vapor collecting in the boiler above the mercury level 13 and passing therefrom through the pipe 14 into the jacket 3 of the vessel or container.

The supply of saturated mercury vapor to the jacket of the vessel 1 is controlled by means of a valve 38. The material is heated by the condensation of the vapor in this jacket, the mercury returnin to the boiler through the catchall 16 The temperature in the jacket of the container or vessel is controlled by the maintenance of a vacuum through the condenser 39 which is cooled by water entering at 40 and leaving at 41. The condensed mercury is returned by means of the pipe 42 through the catchall 16" to the mercurv boiler. Non-condensed gases are removed by pump 43 which discharges into trap 44. This trap is filled with copper or other metal with which mercury forms an amalgam, or a solution with which the mercury will re-act to form a compound.

A pipe coil 45 is arranged in the vessel or container 1, said pipe coil being perforated. A superheater 46 is located in the mercury boiler furnace and is connected by pipe 47 to the coil .45.. The passage of the mercury vapor from the boiler to the superheater 46 is controlled by a valve 48. In this manner it will be seen that highly superheated mercury vapor may be delivered through the perforated pipe coil 45 into the substance being treated and thereby carry off such substance by vapor distillation or vapor sublimation into a series of condensers 49, 50 and 51. These condensers are respectively cooled by a cooling liquid entering at 52, 53 and 54, and leaving at 55, 56 and 57. In the condenser 49, those impurities which have a higher boiling point than mercury are condensed and are intermittently discharged into a vat 60 by the alternate openin and closing of valves 61 and 62. The con enser 50 condenses the mercury together with the material being distilled or sublimed and these condensations fall into a trap 63 from which they are continually delivered into the vat 64. Because of the difference in density of the mercury and other materials, the mercury will seek the lower level in the vat 64 and may be removed through a suitable filter 65, preferably containing a material such as ehamois. From the filter the condensed mercury is delivered into the catchall 16 such return of the mercury being controlled by a valve 66. The trap 63 is sufiiciently deep so as not to interfere with the maintenance of the desired vacuum. The material which has thus been refined and floats on the surface of the mercury in the vat 64 may be removed from said vat through the door 67. The condenser 51 catches any material which may escape the previous condensers and its operation is similar to that of the condenser 49. The vacuum is maintained on the system by means of the pump 69 discharging into a tra 70 which contains a solution reacting with t 1e mercury or a metal amalgamating therewith.

The valve 66 is normally closed and is not usually opened at times when the pressure in the system is materially above or below atmosphere.

As shown in Fig. 1 of the parent case, Serial N 0. 363,129, of which this case is a division, and in my Patent No. 1,403,471, the level of mercury in the boiler should be high enough to submerge the inlet from the catchall 16. This prevents reverse flow of hot mercury vapor from the boiler 7 through the catchall 16 and condenser 39. With the inlet submerged, however, reverse flow of vapor is prevented. If the valve 38 is partly or wholly closed, the liquid mercury merely backs up into the bottom of jacket 3, where it may serve the useful purpose of steadying the temperature by boiling when the jacket is too hot to condense mercury at the existing pressure.

Superheating the mercury vapor that is discharged directly into the substance being treated has the effect of minimizing condensation within the container 1. By regulating the superheat or by regulating the pressure within the container 1, specifically by keeping the pressure and boiling point in the container below that in the jacket 3 all mercury passing into. the container as vapor may be made to pass off as vapor, leaving no residual liquid mercury in the container.

\V'hile the pressures in the two systems are separately controlled as by pumps 43 and 69, these pressures might too easily equalize through the boiler 7, were it not for valves 38 and 48, which can be adjusted so as to make the pressure controls practically independent, though derived from the same boiler. While one boiler is thus the equivalent of two boilers, two may be employed, if desired.

From the above it will be seen that in the operation of the apparatus described, an exceedingly delicate regulation of the temperature, to which the substance being treated is heated, may be obtained. Thus the mercury vapor may be admitted to the jacket of the vessel or container for heating the material by conduction through the wall of the vessel and a superheated mercury vapor may also be delivered directly into the mass of material so that it will be quickly heated throughout to a uniform temperature. This latter operation is particularly employed in the purification of beta naphthol, anthacene, anthraquinone, and similar materials which necessitate the application of an exceedingly high temperature in order to effect the desired chemical reactions. However, I have also applied my improved method to the distillation, fusing, heating, etc., of certain inorganic chemicals.

While I have described mercury as a preferred liquid for practice of my method, it will be evident that the novelty broadly includes distilling a material or substance by projecting into it superheated vapor of a liquid that has a boiling point higher than that of water; that has no chemical affinity for the substance being distilled; that has no capillary attraction with reference to the substance being distilled; and that has specific gravity very much greater than said substance. With these conditions fulfilled, the superheated vapor operates without complications, purely as a heating medium that is molecularly and chemically inert. In the case of mercury, the relatively enormous specific gravity combined with the capillary repulsion of the mercur with respect to the distillate, phenomenal y facilitates separating out of the condensed mercury for re-heating, in continuous cycle.

I claim: 7

1. The. method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface afiinity for mercury, which method consists in subjecting mercury to heat to form a vapor, applying a part of the mercury vapor in heat absorbing relation to a container of the substance being treated, discharging another part of the mercury vapor directly into the substance being treated, to effect the. distillation thereof along with said directly discharged mercury.

2. The method of distilling a vaporizable substance having a vaporization point above that of Water and which has no chemical, solvent or surface affinity for mercury, which method consists in subjecting mercury to heat to form a vapor, abstracting the heat of vaporization from a part of the mercury vapor at the place of utilization of the heat, (lischarging another part of the mercury vapor directly into the substance being treated, agitating the substance to effect the distillation thereof along with said directly. discharged mercury, then condensing the mercury vapor and the distillate, and finally utilizing the weight of the condensed mercury to drain it from the condensed distillate.

3. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface afiinity for mercury, which method consists in subjecting mercury to heat to form a vapor, superheating the mercury vapor and introducing said Vapor into the substance being treated, effecting the distillation of such substance along with said mercury vapor, then condensing the mercury vapor and the distillate, and finally segregating the condensed mercury from the condensed distillate.

4. The method of distilling a vaporizable substance having a vaporization point above that of Water and which has no chemical, solvent or surface affinity for mercury, which method consists in subjecting mercury to heat to form a vapor, supcrheating the mercury vapor and introducing said va or into the substance being treated to there y efl'ect distillation of such substance along with said mercury vapor, then condensing the vaporous impurities in the distillate of higher boiling point, condensing the mercury vapor and the distillate and finally drawing off the condensed mercury from the condensed distillate.

5. The method of distilling a vaporizable substance having a va orization point above that of water and w ich has no chemical, solvent or surface afiinity for mercury, which method consists in subjecting mercury to heat to form a vapor, superheating the mercury vapor and introducing the superheated vapor into the substance being treated to therey efi'ect distillation of such substance along with said mercury vapor, condensing the distillate and the mercury vapor together, removing any incondensed remnant by amalgamation with a metallic agent, and finally segregating the condensed mercury vapor from the condensed distillate.

6. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface atlinity for mercury, which method consists in subjecting mercury to heat to form a vapor, superheating the mercury vapor and introducing the superheated vapor into the substance to cause distillation thereof along with said mercury vapor, condensing the distillate and the mercury vapor, maintaining the heated body of mercury and the condensers under vacuum, and finally segregating the condensed mercury from the condensed distillate.

7. The method of distillin a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface atlinity for mercury, which method consists in subjecting mercury to heat to form a vapor, superheating the mercury vapor and introducing the superheated vapor. into' the substance being treated to thereby eitect distillation of such substance along with said mercury vapor, condensing the distillate and the mercury vapor, maintaining the heated body of mercury and the condensers under vacuum, regulating the vapor temperature by variation of the vacuum, and finally segregating the condensed mercury from the condensed distillate.

8. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface afiinity for mercury, which method consists in subjecting mercury to heat to form a vapor, introducing the mercury vapor into the substance being treated to thereby effect the distillation of such substance along with said mercury vapor, then condensing the various impurities in the distillate of higher boiling point, then condensing the mercury vapor and the distillate, and finally segregating the condensed mercury vapor from the condensed distillate.

9. The method of distilling a vaporizable substance having a vaporization polnt above that of water and which has no chemical, solvent or surface aflinity for mercury, which method consists in subjecting mercury to heat to form a vapor, applying a heating medium in heat absorbing relation to a container of the substance being treated, and discharging the mercury vapor directly into the substance so heated.

10. The method of distilling a va orizable substance having a vaporization point above that of water and which has no chemical, solvent or surface affinity for mercury, which method consists in subjecting mercury to heat to form a vapor, discharging the mercury vapor directly into the substance being treated and agitating the substance to efiect distillation or sublimation therefrom along with said mercury vapor, then condensing the mercury vapor and finally utilizing the welght of the condensed mercury to drain it from the distillate or sublimate.

11. The method of heat treatment of a substance having a vaporization point higher than that of water and which has no chemical, solvent or surface affinity for mercury, which method includes subjecting mercury to heat to form a vapor, superheating the mercuryvapor andintroducing said vapor into the substance being treated and thereby effecting a desired reaction in such substance, then condensing the mercury vapor and finally segregating the condensed mercury from the material treated.

12. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface atiinity for mercury, which method consists in subjecting mercury to heat to form a vapor, introducing said vapor into the substance being treated to thereby effect distillation or sublimation from such substance along with said mercury vapor, then condensing the distillate of higher condensing point than the mercury, then condensing the mercury vapor with the remaining distillate and finally drawing off the condensed mercury from the latter distillate.

13. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface aiiinity for mercury, which method consists in subjecting mercury to heat to form a vapor, introducing the vapor into the substance being treated to thereby effect sublimation from such substance along with said mercury vapor, condensing the sublimate and the mercury vapor together, and finally utilizing the weight of the condensed mercury to separate it from the sublimate.

14. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface aflinity for mercury, which method consists in subjecting mercury to heat to form a vapor, introducing the vapor into the substance in quantities and at temperatures producing distillation or sublimation therefrom along with said mercury vapor while maintaining the heated body of mercury and the condensate under vacuum, and finally segregating the condensed mercury from the condensed distillate.

15. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface affinity for mercury, which method consists in subjecting mercury to heat to boil it, applying the vapor in heat-absorbing relation to the substance being treated and regulating the temperature by regulating the pressure of said vapor; also introducing mercury vapor directly into the substance being treated; and independently regulating the vapor temperature of the latter vapor by regulating its pressure.

16. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface aflinity for mercury, which method consists in subjecting mercury to heat to boil it, applying one part of the mercury vapor to the substance being treated; separately applying another part of the vapor in heat-absorbing relation to said substance, and independently regulating the temperatures of the respective parts of the vapor thus severally applied, by independently regulating their pressures and thereby their boiling and condensing oints.

17. The method of distilling a vaporizable substance having a vaporization point above that of water and which has no chemical, solvent or surface aflinity for mercury, which method consists in subjecting a body of mercury to heat to form a vapor, abstracting the heat of vaporization from a part only of the vapor of the mercury at a point of utilization of the heat, continuously withdrawing the vaporfrom said point of heat application and condensing the mercury, and then removing any uncondensed remnant by amalgamation with a metallic agent.

18. The method of vaporizing a vaporizable substance having a vaporization point higher than that of water, which method includes vaporizing and heating above said vaporization point, a liquid that is of much greater specific gravity than the substance to be distilled, that has no chemical or solvent afiinity for said substance and that does not wet the same; discharging said vapor as a heating medium directly into a body or mass containing said substance; maintainin the temperature to evaporate and drive 0 such substance and said heating medium, as a vapor mixture; abstracting heat from said mixture to condense the constituents thereof and utilizing the weight of the condensed heat-applying liquid, to separate it from the condensed substance.

Signed at New York city, in the county of New York and State of New York, this 14th day of July, 1922.

CROSBY FIELD. 

